Thinking In Metric
David Megginson wrote an interesting entry about flying and the metric system. Canada’s close proximity to the United States has basically resulted in three groups of people when it comes to use of metric in Canada. There are those who grew up with only Metric, those who grew up with imperial and those who grew up in the area of ambiguity, when both systems were being used. The first group of people will likely think in metric in almost all cases, the middle group likely still thinks in imperial and the last group will think one or the either depending on the situation. The last group will also include those people who are forced to used the imperial system due to jobs or hobbies.
I fall into the last category on multiple levels: I started counting in the late 70’s and as such got a mix of both systems. Then I got my pilot licence when I was 19 which means that I can easily measure heights in ‘feet’ but struggle with those same heights in ‘metres’. What I end up doing is estimating a height in feet and then converting it to metres. The same is true for me when I go diving. In North America everything when diving is done with imperial measurements; depths are in feet and air pressure is in PSI.
Most other stuff though, I can envision in metric without thinking. Distance, speeds, volumes, etc are all easy to envision in metric. To that end, I’m trying to fully convert myself to metric. I’ve switched my dive computer to use metric so that while others are talking about dive to 100 feet and only having 500 psi of air left, I’m talking about a dive to 30.5 metres and having 34 bar of air. But I stll have trouble envisioning the actual depth without first converting it to feet and I’m not sure I’ll ever fix that.
Interestingly enough, when it comes to flying I’m totally mixed up. Despite many hours of flying I can’t envision speeds in knots unless they are relative. For example, when I think about a 767’s Vr of 140 knots I can easily relate it as almost 3 times the Vr of the Piper Warrior, but I can’t really envision 140 knots until I convert it to 259 kilometers/hour. Coincidentally, 259 km/hr is the fastest speed I ever got to on my CBR 600 F4i when I still rode motorbikes. I don’t think I’ll ever be able to ‘think’ in knots unless I start measuring distances in nautical miles and that seems like a backwards step given that only three countries in the world aren’t using the metric system.
As for aviation, the mismash of units (I love David’s example of six mile visibility) is a great example of what happens when there is a lack of standards. One day I think we will fly using the metric system, but I can’t see it happening until the US decides to adopt it and I can’t see it happening without a fight (look at the fight that’s going on with respect to the new ELT frequency).
Mon, 31 Oct 2005 15:02 Posted in General
